At the top of the list is inaction on climate change, alongside disparities in income and the failure of governments to reduce their debts.

As the report points out, the fact that the top three risks are exactly the same as in 2012 reflects the tragic failure of policymakers across the globe to make progress on the major economic, environmental and social challenges of our time.

It also recognises that as long as the economy alone dominates the political agenda, the risk of irreversible ecological devastation grows ever greater – which in turn, poses a huge threat to economic stability.

The UK has an invaluable opportunity to show that it understands the nature of these risks as it takes over the presidency of the G8 group of nations.

While there are very real concerns that the G8 itself suffers from a lack of legitimacy, it is nonetheless the case that, over the next 12 months, we have an opportunity to play a key role in shaping multilateral action between the most powerful economies.

For David Cameron, this is a rare chance to rise above the petty squabbles of domestic politics and demonstrate that Britain is fit to provide leadership on the big global issues.

A fairer tax system and transparent governance are certainly worthy priorities. Indeed, both are absolutely crucial if nations are to deliver equality, prosperity and legitimacy for their people.

"Open economies" sounds rather more disturbing; the prime minister's desire to "unleash the power of the private sector" ringing alarm bells about this government's wrong-headed approach to aid and trade with developing countries.

But after a year that will be remembered for the devastation wreaked by hurricane Sandy, flooding in China and, of course, here at home, and raging wildfires in Australia, it's simply baffling – and irresponsible in the extreme – for the leader of the world's sixth-biggest economy to fail to assert his commitment to leading on climate change.

New figures from the Global Carbon Project and the Tyndall Centre for Climate Change Research released during the UN climate negotiations in Doha showed that global carbon dioxide emissions were set to rise again in 2012, reaching a record high of 35.6bn tonnes.

Prof Corinne Le Quéré, director of the Tyndall Centre, has remarked that "with emissions continuing to grow, it's as if no one is listening to the entire scientific community".

Yet it's not as if the government itself doesn't recognise the dire impacts of climate change –particularly on developing countries.

When I quizzed the Department for International Development last year about the potential effect of extreme weather events on its objectives of alleviating hunger and poverty in the global south as temperatures increase, minister Alan Duncan referred to projections that 375 million people a year will be affected by climate-related disasters by 2015.

If the government wants the UK to be taken seriously as a responsible player on the global stage, the prime minister should rectify the deplorable omission of climate change from his G8 priorities now – and go to the summit in June with his own strong vision of how to tackle it.